1. Field of the Invention
The present invention relates to a technique of an X-ray image diagnostic apparatus.
2. Background Art
Medical image diagnosis using an X-ray image diagnostic apparatus, an X-ray CT (Computed Tomography) apparatus, or the like has rapidly progressed with the development of computer technology, and has become indispensable in today's medical treatment. In particular, X-ray image diagnosis of cardiovascular region, which has progressed with the development of the catheter procedure, is widely used for the arteries and veins of the whole body including a cardiovascular system.
The X-ray image diagnostic apparatus for the diagnosis of cardiovascular region includes an X-ray generation unit and an X-ray detection unit (hereinafter, these are referred to collectively as an imaging system), a holding unit such as a C arm that holds an imaging system, a top plate on which a patient is placed, and the like. By moving the imaging system fixed to the top plate or the holding unit in a desired direction, it is possible to perform X-ray imaging from an optimal direction for a treatment site of the patient.
On the other hand, minimally invasive treatment called MIT has been drawing attention in recent years. As a representative MIT for a patient with heart disease or ischemic brain disease, a so-called intervention treatment that uses a catheter or the like under observation of the image data may be mentioned.
Examples of a device for endovascular treatment (hereinafter, referred to as a treatment device) used in the treatment of cerebral blood vessel, cardiac blood vessel, peripheral blood vessel, and the like in which stenosis has occurred due to the deposition of cholesterol on the inner wall include a balloon catheter which expands a stenotic portion in a radial direction, a stent for maintaining the blood vessel diameter expands by the balloon, and DCA (directional coronary atherectomy) or a rotablator which excises the plaque of a stenotic portion by moving or rotating a micro cutter fixed to the tip of the catheter within the blood vessel.
In addition, a method has been adopted in which the position of such a treatment device in the blood vessel is specified by observing the image data obtained in real time when continuously performing X-ray imaging in a fluoroscopic imaging mode for a patient to whom the treatment device is inserted.
According to such a method, however, X-ray irradiation to the patient is performed over a long period of time. Therefore, there has been a problem in that the exposure dose increases. In addition, in order to solve such a problem, a method has been adopted in which, for example, one item of image data (reference image data) is collected by X-ray imaging for a patient to whom a contrast agent is injected and then the position information of a treatment device, which is supplied in time series from a position detector of the treatment device inserted into the body of the patient, is sequentially superimposed on the reference image data, and the result is displayed.
According to the above-described method of superimposing the position information of the treatment device measured separately on the reference image data collected in advance and displaying the result, it is possible to significantly reduce the exposure dose to the patient during medical treatment. However, since the position detector provided in the treatment device does not usually have sufficient accuracy, there is a problem in that it is difficult to correctly check the position information of the treatment device inserted into the blood vessel.